Nice Layout...
What is the question here? I didn't see one.
If your question is: "Is it going to matter is one gate trace length is 2cm longer than the other?" then the answer is "no" with consideration of the switching frequency. The addition of gate resistors pretty much stops parasitic oscillations from ever reaching the FET gates. What's your switching frequency?
What is the question here? I didn't see one.
If your question is: "Is it going to matter is one gate trace length is 2cm longer than the other?" then the answer is "no" with consideration of the switching frequency. The addition of gate resistors pretty much stops parasitic oscillations from ever reaching the FET gates. What's your switching frequency?
The pulldown resistors are definitely the answer here.
But I noticed another problem area: your XF core.
Using surplus or recovered parts is a great satisfacton for a hobyist.
However, using an unknown core for the power X-former in a hi-powered SMPS is the worst idea. It's just like using an unmarked capacitor or resistor, and having no way to measure it's value, but throwing it in the circuit anyways.
Most core materials you're likely to find in recovered inductors are not made to the stringent requirements needed for a hi frequency power transformer core.
You'll find that ferrite cores for really powerful high frequency transformers (200-500 W and higher) are not easy to come by.
Furthermore, Push-pull designs are prone to core walk-up if even the smallest asymmetry exists between the driver transistors, saturating even a well-calculated core.
Your best bet, if you want surplus, is to cannibalize an existing SMPS, and use the power x-former from that circuit as your core (strip the windings, and rewind). You need to make sure that:
1. the SMPS you're stripping was rated for at least the same power output as your design.
2. know what topology the surplus SMPS was using, ie if it was flyback, expect an air gap in the transformer core. If your topology is push-pull or forward, then the gap won't do. Pay attention to that. You may be able to change your design to a flyback just to use a desirable gapped core, if that's what's available.
But don't use any cores that served a function other than of power XF in an SMPS, because those cores can and will screw around with your head.
But I noticed another problem area: your XF core.
Using surplus or recovered parts is a great satisfacton for a hobyist.
However, using an unknown core for the power X-former in a hi-powered SMPS is the worst idea. It's just like using an unmarked capacitor or resistor, and having no way to measure it's value, but throwing it in the circuit anyways.
Most core materials you're likely to find in recovered inductors are not made to the stringent requirements needed for a hi frequency power transformer core.
You'll find that ferrite cores for really powerful high frequency transformers (200-500 W and higher) are not easy to come by.
Furthermore, Push-pull designs are prone to core walk-up if even the smallest asymmetry exists between the driver transistors, saturating even a well-calculated core.
Your best bet, if you want surplus, is to cannibalize an existing SMPS, and use the power x-former from that circuit as your core (strip the windings, and rewind). You need to make sure that:
1. the SMPS you're stripping was rated for at least the same power output as your design.
2. know what topology the surplus SMPS was using, ie if it was flyback, expect an air gap in the transformer core. If your topology is push-pull or forward, then the gap won't do. Pay attention to that. You may be able to change your design to a flyback just to use a desirable gapped core, if that's what's available.
But don't use any cores that served a function other than of power XF in an SMPS, because those cores can and will screw around with your head.
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